what metals are used for heatsinks?

[armadillo]

I know aluminium and copper are the most common. I have seen a few coolers that look like stainless steel. But it could not be, as the thermal conductivity of stainless steel is much less than aluminium. So is there some exotic alloy that conducts heat well?
 

[Dark Mantis]

Hi

The best thermal conductor is silver but for obvious reasons this isn't used much for heatsinks. Next comes copper and then alluminium. Both of these can be made into various alloys by mixing other metals with them. This is more common with aluminium for cooler use. I don't think that the one you were looking at was made of stainless steel as apart from not being so efficient it is much more difficult to work with.